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81.
The Pinus genus has an elevated pollen production and an anemophilous nature. Although considered to be hypoallergenic, numerous cases
of allergies caused by Pinus pollen have been cited and different authors believe that its allergenicity should be studied in more depth. In the city
of Vigo several patients have tested positive for Pinus pollen extracts in skin tests, some of them being mono-sensitive to such pollens.
In order to ascertain the behaviour of Pinus pollen and its correlation to the main meteorological factors, we carried out an aerobiological study in the city of Vigo
from 1995 to 1998 by using a Hirst active-impact volumetric sporetrap, model Lanzoni VPPS 2000, placed on the left bank of
the Vigo estuary (42°14’15’’N, 8°43’30’’W). Pinus has high quantitative importance in the airborne pollen spectrum of the city. It is one of the best represented taxa constituting
13%–20% of the total annual pollen levels. The quantity of Pinus pollen present in the atmosphere of the city of Vigo throughout a year is 5751 grains (as the average for the sampled years),
with a very long pollination period, from the middle of January until May. The maximum concentration was recorded in 1998
with 1105 grains/m3 on 3 March, a much greater value than those for the previous years. At the end of its pollination period there is usually
a final increase in Pinus pollen concentrations coinciding with the pollination of Pinus silvestris, which are more abundant in mountainous areas far from the city.
Received: 17 March 1999 / Revised: 20 December 1999 / Accepted: 20 December 1999 相似文献
82.
M?Alejandra?Perotti Silvia?S?Catalá Analía?del?V?Orme?o Monika??elazowska Szczepan?M?Biliński Henk?R?BraigEmail author 《BMC genetics》2004,5(1):10
Background
At the turn of the 19th century the first observations of a female-biased sex ratio in broods and populations of the head louse, Pediculus humanus capitis, had been reported. A study by Buxton in 1940 on the sex ratio of lice on prisoners in Ceylon is still today the subject of reanalyses. This sex ratio distortion had been detected in ten different countries. In the last sixty years no new data have been collected, especially on scalp infestations under economically and socially more developed conditions.Results
Here we report a female bias of head lice in a survey of 480 school children in Argentina. This bias is independent of the intensity of the pediculosis, which makes local mate competition highly unlikely as the source of the aberrant sex ratio; however, other possible adaptive mechanisms cannot be discounted. These lice as well as lice from pupils in Britain were carrying several strains of the endosymbiotic bacterium Wolbachia pipientis, one of the most wide spread intracellular sex ratio distorters. Similar Wolbachia strains are also present in the pig louse, Haematopinus suis, suggesting that this endosymbiont might have a marked influence on the biology of the whole order. The presence of a related obligate nutritional bacterium in lice prevents the investigation of a causal link between sex ratio and endosymbionts.Conclusions
Regardless of its origin, this sex ratio distortion in head lice that has been reported world wide, is stable over time and is a remarkable deviation from the stability of frequency-dependent selection of Fisher's sex ratio. A female bias first reported in 1898 is still present over a hundred years and a thousand generations later.83.
María Jesús Aira Francisco-Javier Rodríguez-Rajo María Fernández-González Carmen Seijo Belén Elvira-Rendueles Montserrat Gutiérrez-Bustillo 《Grana》2013,52(4):293-304
Cladosporium spores are ubiquitous in the air and are included in the fungal contaminants that define environmental quality. This paper provides an updated review of their concentration in the Iberian Peninsula, based on data from 12 sampling stations collected using a common non-viable volumetric sampling method and the same subsequent data-treatment techniques. The database comprised 84 annual periods, covering the period 1993–2009. Mean annual total spore concentrations for each station, calculated as the sum of daily concentrations, ranged from 54 459 in Cartagena to 933 485 in Sevilla; other sampling stations recorded annual total spores between 93 052 (Porto) and 579 953 (Mérida). Analysis of annual spore-distribution patterns revealed either one or two peaks (spring and fall) depending on the location and prevailing climate of the area where the sampling stations have been placed. For all stations, average temperature was the meteorological parameter displaying the strongest positive correlation with airborne spore concentrations. 相似文献
84.
去除基部果枝对不同基因型棉花部分早衰特征的影响 总被引:1,自引:0,他引:1
以9个不同基因型棉花(GossypiumL.)为材料,通过去除基部2个果枝调节源库比例,研究在生殖生长初期调节源库比例对不同基因型棉花部分早衰特征的影响。结果显示:(1)在生殖生长初期调节源库比例对供试9个棉花品种的冠层底部光合有效辐射(TPAR)、叶面积系数(LAI)、不同结铃期所结棉铃对位果枝叶SPAD值变化率、棉铃脱落率、红茎比率及单铃重均有较大的影响,处理间差异达到显著(P<0.05)或极显著(P<0.01)水平,且随着生育进程的推进,去除基部果枝对延缓早衰的作用更为显著。(2)对于不同基因型棉花,改变生殖生长初期源库比例延缓早衰的效应存在一定差异,去除基部果枝对于‘冀杂999’、‘国抗34’和‘荃银2号’3个品种早衰现象的延缓效应最好,而‘川杂棉33’居中,‘鲁HB标杂-1’等5个品种延缓效应较差。研究表明,在生殖生长初期去除基部果枝对棉花早衰有延缓作用,其效应大小在棉花基因型间存在差异。 相似文献
85.
Martinac M Ebling B Dujsin M Majstorović K Jurcić D Bilić A Perić RT 《Collegium antropologicum》2011,35(2):505-512
Constipation is a common problem in children. It can be a symptom of functional disorder in majority of cases, but sometimes a serious organic disease is a cause of constipation. Anorectal manometry plays an important role in the diagnostic procedure. It can be presumed that some values of manometric parameters could be very useful in treatment plan. The aim of this study was to confirm or exclude such limits in manometric finding, to make a plan of the therapy more accurate. Therefore the group of 81 constipated children was investigated. There were 58 patients suffering from functional constipation and 23 with organic disorders. The age of the patients was 3 to 15 years. Scoring system was applied to estimate severity of constipation and anorectal manometry was performed. Our results did not show significant correlation between clinical symptoms and signs and the values that we obtained using anorectal manometry. But, we recommend anorectal manometry because it is a safe method and contributes to clarify the diagnosis, which is very important for treatment plan. 相似文献
86.
Kozina V Geist D Kubinová L Bilić E Karnthaler HP Waitz T Janáček J Chernyavskiy O Krhen I Ježek D 《Histochemistry and cell biology》2011,135(2):215-228
Within the human testis, Reinke’s crystals are found in Leydig cells but their nature and function are poorly understood.
The aim of our study was to investigate the properties of Reinke’s crystals in man with the normal morphology of the testis
(control group) and infertile patients diagnosed with cryptorchidism. 20 biopsies from infertile patients and six biopsies
from men with regular spermatogenesis (20–30 years.) were used. Sections of the testis tissue were stained with haematoxylin
and eosin and a modified Masson’s method. Specimens were observed by bright field, confocal and transmission electron microscopy
(TEM). The number of Reinke’s crystals in investigated groups was determined applying stereological methods. In both groups,
Reinke’s crystals were noted within the cytoplasm and nuclei of Leydig cells. Some “free” crystals were found within the interstitial
space, outside Leydig cells. Confocal microscopy proved to be very useful in the assessment of the shape and 3D reconstruction
of the crystal. TEM analysis confirmed a hexagonal form of the crystal, while crystallographic data on sections of 70–300 nm
thickness provided a better insight into the organization of the crystal lattice. Stereological analysis revealed a significant
increase in the number of crystals in cryptorchid testes when compared with controls. Increased number of crystals in cryptorchid
specimens leads to the assumption that the prolonged exposure to higher (abdominal) temperature might stimulate enzymes involved
in the synthesis of the proteins of the crystal. However, the exact molecular nature of the crystal lattice remains in both
normal and cryptorchid testis obscure. 相似文献
87.
The effects of cryptorchidism on the regulation of steroidogenesis and gap junctional communication in equine testes 总被引:2,自引:0,他引:2
INTRODUCTION: Evidence collected over the years has demonstrated that cryptorchidism is associated with a defect in spermatogenesis and, as a consequence, with either reduced fertility or infertility. However, the effect of cryptorchidism on Leydig cell function is less clear. The aim of our study therefore was to investigate the regulation of steroid hormone biosynthesis and, additionally, intercellular communication in the cryptorchid equine testes. MATERIAL AND METHODS: Testes of mature bilaterally cryptorchid horse and healthy stallions were used for this study. The expression of luteinising hormone receptor (LHR), 3beta-hydroxysteroid dehydrogenase (3beta-HSD), aromatase and connexin43 (Cx43) was detected by means of immunohistochemistry. Testosterone and oestradiol levels were measured in testicular homogenates using appropriate radioimmunoassays. RESULTS: In the testes of both normal and cryptorchid stallions, immunostaining for LHR, 3beta-HSD and aromatase was confined to the Leydig cells. In the cryptorchid horse, the intensity of the staining for LHR and 3beta-HSD was weaker, whereas the staining for aromatase was clearly stronger than that of the normal stallion. Radioimmunological analysis revealed disturbance of the androgen-oestrogen balance in the cryptorchid testes. Additionally, in both the seminiferous tubules and interstitial tissue of the cryptorchid a clear reduction of the Cx43 signal was observed. CONCLUSIONS: Decreased expression of LHR and 3beta-HSD and increased expression of aromatase in the cryptorchid testes suggest that hormonal imbalance was caused both by reduced testosterone synthesis and by increased androgen aromatisation. Impaired expression of Cx43 in the seminiferous tubules as well as in the interstitial tissue of the cryptorchid horse indicates that cryptorchidism affects intercellular communication in the testes. 相似文献
88.
Jurcić D Bilić A Schwarz D Orsanić D Gabrić M Spoljarić L Mihanović M 《Collegium antropologicum》2008,32(3):771-775
One hundred and thirty-one patients on long-term hemodialysis were examined for the presence of clinical symptoms and signs, and for the effects of dialytic age, age and sex on uremic neuropathy. According to dialysis age, the patients were divided into three subgroups: low dialysis age, < 5 years of dialysis (n = 58); intermediate dialysis age, 5-10 years of hemodialysis (n = 39); and high dialysis age, > 10 years of dialysis (n = 34). Two patient subgroups were differentiated according to mean age of 53.2 years: younger (n = 57) and older (n = 74). Clinical grading of uremic neuropathy was based on Nielsen's criteria. The most common symptoms were restless legs syndrome (47%) and cramps (51%). Sensory symptoms were less common in patients on long-term hemodialysis, most common of them being paresthesia (29%) and burning feet syndrome (28%). Abnormal Achilles reflex (53%) and impaired vibration sense (59%) were the most common clinical signs. Clinically manifested uremic neuropathy was present in more than 80% of all study patients, i.e. mild in 41%, and moderate to severe forms of uremic neuropathy according to Nielsen's criteria in 39%. There was no evident effect of dialytic age and sex on the clinical course of uremic neuropathy, however, there was a clear impact of age. It is concluded that long-term hemodialysis does not influence the clinical course of uremic neuropathy unlike evident deterioration of electroneurophysiologic findings. 相似文献
89.
BAC libraries construction from the ancestral diploid genomes of the allotetraploid cultivated peanut 总被引:1,自引:0,他引:1
Patricia M Guimarães Olivier Garsmeur Karina Proite Soraya CM Leal-Bertioli Guilhermo Seijo Christian Chaine David J Bertioli Angelique D'Hont 《BMC plant biology》2008,8(1):14
Background
Cultivated peanut, Arachis hypogaea is an allotetraploid of recent origin, with an AABB genome. In common with many other polyploids, it seems that a severe genetic bottle-neck was imposed at the species origin, via hybridisation of two wild species and spontaneous chromosome duplication. Therefore, the study of the genome of peanut is hampered both by the crop's low genetic diversity and its polyploidy. In contrast to cultivated peanut, most wild Arachis species are diploid with high genetic diversity. The study of diploid Arachis genomes is therefore attractive, both to simplify the construction of genetic and physical maps, and for the isolation and characterization of wild alleles. The most probable wild ancestors of cultivated peanut are A. duranensis and A. ipaënsis with genome types AA and BB respectively.Results
We constructed and characterized two large-insert libraries in Bacterial Artificial Chromosome (BAC) vector, one for each of the diploid ancestral species. The libraries (AA and BB) are respectively c. 7.4 and c. 5.3 genome equivalents with low organelle contamination and average insert sizes of 110 and 100 kb. Both libraries were used for the isolation of clones containing genetically mapped legume anchor markers (single copy genes), and resistance gene analogues.Conclusion
These diploid BAC libraries are important tools for the isolation of wild alleles conferring resistances to biotic stresses, comparisons of orthologous regions of the AA and BB genomes with each other and with other legume species, and will facilitate the construction of a physical map.90.
With the aim to know the importance of theCastanea pollen in the Galician honey(N. W. Spain), the interannual oscillations withinthe areas of production and the most activephenological period for bees, we have madethe melissopalynological analysis of: 599samples of honey collected during the period1990–1999 in Galicia, the production of 40beehives during three consecutive years(1990, 1991, 1992), the partial production during1990 of two beehives situated at distant pointsin our geography. 相似文献